1. Field of the Invention
The present invention relates to an apparatus and a method for processing an informational signal and a program for performing the method therefor. More particularly, it relates to an apparatus for processing an informational signal such as TV receiver and the like.
2. Description of Related Art
Owing to increasing audio-visual oriented requirements in recent years, there has occurred a demand for a TV receiver that can obtain an image having a higher resolution, to meet which demand, a so-called high-definition TV (HDTV) has been developed. The HDTV has 1125 scanning lines, which number is more than twice the number of the scanning lines of 525 for an NTSC-scheme TV. Further, the HDTV has an aspect ratio of 9:16 in contrast of an aspect ratio of 3:4 of the NTSC-scheme TV. Therefore, the HDVT can display an image that has higher resolution and realistic sensations than the NTSC-scheme TV.
Although the HDTV has such excellent properties, it can display no images only by receiving an NTSC-scheme video signal as it is. This is because the NTSC-scheme TV and the HDTC have different standards as described above.
In view of the above, a converter for converting an NTSC-scheme video signal into an HDTV video signal in order to display the HDTV-scheme image in accordance with the NTSC scheme video signal has been disclosed (see Japanese Patent Application Publication No. H08-51599).
In such the converter, pixel data of a block (region) that corresponds to pixel data of a target position in a HDTV video signal is extracted from an NTSC-scheme video signal, so that based on a level distribution pattern of the pixel data of this block, a class to which the pixel data of this target position belongs is determined, in accordance to which class the pixel data of this target position is generated.
In this converter, a resolution of an image owing to an HDTV video signal is fixed. A user cannot give his or her preferred resolution that matches image contents etc. in contrast to the case of conventional adjustment of a contrast, sharpness, etc.
To solve this problem, has been proposed an apparatus for processing an informational signal that, when converting an NTSC-scheme video signal into an HDTV video signal, a user can generate the HDTV video signal in accordance with a value of an input parameter to freely adjust a resolution etc. of an image obtained by this HDTV video signal (see Japanese Patent Application Publication No. 2001-238185).
However, in such the apparatus for processing the informational signal, the user can freely adjust a resolution of an image, while its adjustment range is fixed. If a user makes adjustments mainly, for example, to one end side of this adjustment range, he or she cannot have a sufficient adjustment range. Therefore, it is desired that adjustments can be made that match the user's preferences.
It is an object of the present invention to provide an apparatus for processing an informational signal and the like that enables a final adjustment value obtained by user operations to be more efficiently utilized, thereby accurately making adjustments that match, for example, user preferences.